A digital transformation, brought about through the power of connectivity, is taking place in almost every industry. Through an unprecedented ability to share information, people and industries are collaborating more, creating solutions that combine many different areas of expertise and overturning traditional business models. But the pressure on the networks that provide this connectivity is palpable. For that reason, a new system (the “5G system”) will be built to enable logical network slices, which will enable operators to provide networks on an as-a-service basis and meet the wide range of expected use cases. See e.g., “5G White Paper,” by the NGMN Alliance (available at web.archive.org/web/20150319062242/http://www.ngmn.org/uploads/media/NGMN_5G_White_Paper_V1_0.pdf); see also Ericsson, “5G Systems White Paper,” January 2015 (available at web.archive.org/web/20151012184616/http://www.erics son.com/res/docs/whitepapers/what-is-a-5g-system.pdf); and Ericsson, “The Real-Time Cloud White Paper”, February 2014 (available at web.archive.org/web/20140309031847/http://www.erics son.com/res/docs/whitepapers/wp-sdn-and-cloud.pdf)
Traditional, one-size-fits-all network architectures with purpose-built systems for support and IT worked well for single-service subscriber networks with predictable traffic and growth. However, the resulting vertical architecture has made it difficult to scale telecom networks, adapt to changing subscriber demands and meet the requirements of emerging use cases. Cloud technologies together with software-defined networking (SDN) and Network Functions Virtualization (NFV) provide the tools that enable architects to build systems with a greater degree of abstraction, which enhances network flexibility. Cloud, SDN and NFV technologies allow vertical systems to be broken apart into building blocks, resulting in a horizontal network architecture that can be chained together—both programmatically and virtually—to suit the services being offered and scaled. In 5G systems, networks will be further abstracted into network slices: a connectivity service defined by a number of customizable software-defined functions that govern geographical coverage area, duration, capacity, speed, latency, robustness, security and availability.